Disinfection agent for suction systems used in the field of medicine

ABSTRACT

A thickened, ready-for-use disinfectant for medical or dental suction apparatus, said disinfectant including a special active substance of amine compounds with a viscosity between 100 and 2000 mPa.s, preferably between 350 and 1000 mPa.s.

The present invention is in the field of disinfection for suction apparatus in the medical sector. It relates to disinfectants for medical or dental suction apparatus and is also directed to methods of maintaining such apparatus and to the use of such disinfectants to destroy bacteria and/or fungi in such suction apparatus.

Especially in the medical sector it is necessary to take all reasonable measures to ensure safety of patients by preventing possible transmission of pathogenic or optionally pathogenic germs and avoid nuisance by odor-producing bacteria.

One possible center of growth of such germs is represented by suction apparatus in the medical sector, which therefore require regular cleaning and disinfection. For example, a mixed stream of air, water, saliva, tooth substance and the like is sucked out of the patient's mouth by means of dental suction apparatus, the air is separated therefrom, and the rest is led to a drain. Components of the mixed stream, in particular also bacteria, blood residues and other contaminations deposit in the suction tubes and pipes. Rinsing or other treatment with disinfectant-water mixtures at regular intervals is intended to satisfy the requirements of hygiene. For disinfection purposes, liquid disinfectant concentrates based on quaternary ammonium compounds have normally been employed up to now, which concentrates are diluted prior to use. The disadvantage of this method is the insufficient residence time of the disinfecting solution in the suction apparatus, trickles forming due to flow-related circumstances, thereby preventing uniform wetting of the inner surfaces of the tubes. In addition, the quaternary ammonium compounds that are employed have not more than a limited spectrum of activity against bacteria, fungi and enveloped viruses. In particular, these active substances fail to ensure effectiveness towards mycobacteria.

Another possible prior art use is the use of powdered or granulated disinfectants according to DE 40 10 615. When used following previous wetting of the suction system, a longer residence time and sufficient, uniform wetting is possible in the method according to DE 40 10 615. However, the disadvantage of this method lies in ensuring a homogeneous distribution of the disinfectant active substance in the product mixture employed, which includes further solid formulation components such as builders, cleaning components and other constituents. The demanded homogeneity and stability of the powder mixture or granulate can only be achieved by means of technically complex processes. Another drawback is the limited selection of possible microbicidal agents, because solid substances such as quaternary ammonium compounds or salts of chloroisocyanuric acid or of tosylchloroamide are preferably put to use. The disadvantages of using quaternary ammonium compounds have already been described. On the other hand, chlorine-containing active substances are AOX-forming substances whose discharge into municipal sewage systems is restricted. According to the invention, AOX-forming substances are understood to be compounds which may result in the formation of organic halogen compounds adsorbable on activated carbon.

Accordingly, it was the object of the present invention to provide a disinfectant for suction apparatus, which would establish uniform distribution of the active substances within the suction apparatus and ensure sufficient residence time for the destruction or inactivation of an extensive germ spectrum, especially of mycobacteria and adenoviruses.

Consequently, the present invention is directed to a thickened, ready-for-use disinfectant for medical or dental suction apparatus, which includes an active substance selected from the group of alkylpropylenediamines of general formula I

wherein R¹ represents an alkyl or alkenyl group with 8 to 18 carbon atoms and R² represents hydrogen, an alkyl group with 1 to 4 carbon atoms or an aminoalkyl group with 2 to 4 carbon atoms, and/or from the group of products known as Glucoprotamin®, as obtained from an alkylpropylenediamine of formula II R³—NH—CH₂—CH₂—CH₂—NH₂   (II) wherein R³ represents a linear alkyl group with 12 to 14 carbon atoms, by reaction with compounds of formula III

wherein R⁴ represents hydrogen or an alkyl group with 1 to 4 carbon atoms, at a molar ratio of from 1:1 to 1:2 at 60 to 175° C., characterized in that the ready-for-use agent has a viscosity between 100 and 2000 mPa.s, preferably between 350 and 1000 mPa.s, measured with a Brookfield digital viscometer, model LVTDV-II at a sample temperature of 20° C. using a spindle No. 2 (LV series, code number 62) at a spindle rotation of 12 revolutions/minute, the value being read after 60 seconds. Ready-for-use means that the agent immediately introduced into the suction apparatus has the above-mentioned properties.

The disinfectant according to the invention preferably includes Glucoprotamin®, N,N-bis(3-aminopropyl)laurylamine, N-dodecyl-1,3-propanediamine, N-coco-1,3-propanediamine or a mixture thereof as active substance mentioned above.

The disinfectant according to the invention preferably includes from 0.01 to 30 wt.-%, particularly from 0.1 to 15 wt.-%, relative to the overall agent, of one or more of the above-mentioned active substances.

In another preferred embodiment the disinfectant of the invention additionally includes a second active substance selected from the group of quaternary ammonium compounds of formula I

wherein R⁵ represents an alkyl group with 6 to 16 C atoms, R⁶ represents an alkyl group with 1 to 12 C atoms or a benzyl group, R⁷ and R⁸ represent alkyl groups with 1 to 4 C atoms or hydroxyalkyl groups with 2 to 4 C atoms, and A⁻ represents an equivalent amount of a corresponding anion.

Particularly preferred active substances in accordance with formula I are benzalkonium chloride and/or dimethyldioctylammonium chloride.

Furthermore, the disinfectant according to the invention preferably includes 0.01 to 30 wt.-%, especially 0.1 to 15 wt.-% of said second active substance, relative to the overall agent.

The advantage of the present inventive disinfectant is that following use, it forms a continuous layer on the inner surface of the suction tubes or pipes, said layer substantially resisting complete deliquescence during a specific period of time which depends on the viscosity of the disinfectant. Therefore, a disinfectant present in liquid form is not a composition in the meaning of the present invention because such a solution deliquesces almost instantaneously upon introduction into the suction apparatus.

Another precondition is that the disinfectant of the invention can be washed off after application and working in.

In principle, any gel comprised of a dispersed phase and dispersant can be used as base of the formulation, provided the components would not undergo undesirable reaction with the active components of the invention. In a preferred fashion gels based on water are used, especially water-based gels with dispersed organic gel-forming agents. For example, gels as described in the unexamined German application DE-OS 38 36 138 can be used. Hydrophilic organic gels based on modified fatty alcohol alkoxylates and polymers produced by synthesis, preferably gels based on polyvinyl alcohol or polyacrylic acid derivatives are particularly preferred.

Preferred commercially available thickeners are the raw materials Optiflo® H 600/E from SÜD-CHEMIE and PLURIOL A 5000 T 85 from BASF. Optiflo H 600/E is a non-ionic, hydrophobic-modified polymer, and PLURIOL A 5000 T 85 is a modified fatty alcohol ethoxylate.

However, other thickeners such as carboxymethylcellulose, non-ionically and cationically modified polyacrylate are also possible.

In addition, the formulation may include conventional additives such as coloring components, odorous substances, etc.

To produce the disinfectants of the invention, the components are mixed together. Thus, the solvent, preferably water, the active components, as well as thickeners, thixotropic agents, gel-forming agents or film-forming agents, optionally surfactants, especially low-foam surfactants, and other auxiliary agents such as defoamers, corrosion inhibitors and complexing agents can be mixed together.

The disinfectant, which is ready-for-use according to the invention, preferably has a pH value of from 8 to 12, more preferably from 9 to 11.

Furthermore, the disinfectant of the invention preferably includes one or more additional components other than those mentioned above and selected from the group of tertiary amine oxides, anionic surfactants, ether sulfates, alkylpolyglycosides, cationic surfactants, non-ionic surfactants, amphosurfactants, silicone defoamers, cumenesulfonate, xylenesulfonate, toluenesulfonate, hydrophobically modified polymers, diluents, chelating agents, enzymes, preservatives, sequestering agents, oxidizing (bleaching) agents, dyes and/or perfumes.

In particular, low-foam non-ionic surfactants such as fatty alcohol alkoxylates with an alkyl group having 8 to 22 C atoms, end group-capped or not, or well-known thickener amine oxides are predominantly used as surfactants. When using anionic surfactants, the amounts employed will be low due to their foaming behavior and their compatibility with cationic active agents and/or glucoprotamin, so that the use thereof would not give rise to complaints.

The present invention is also directed to a method for the maintenance of a medical or dental suction apparatus, particularly the suction tube thereof, in which method an inventive disinfectant is introduced into the suction area.

Furthermore, the present invention is directed to the use of an inventive disinfectant to destroy bacteria, especially mycobacteria and/or fungi, in medical or dental suction apparatus, particularly in the suction tube thereof and in the spitting cup.

The following examples are intended to illustrate the invention in more detail, without limiting the scope thereof.

EXAMPLES Example 1

Production of a disinfectant gel according to the invention

-   -   a) 18 g of carboxymethylcellulose were sprinkled into 950 g of         water, added with 1.0 g of a 50 wt.-% potassium hydroxide         solution and mixed with stirring.     -   b) After completion of the carboxymethylcellulose swelling         process (2-5 hours), the solution produced under a) was added         with 8 g of a 50 wt.-% Glucoprotamin® solution, 5 g of a 70         wt.-% solution of dioctyldimethylammonium chloride in a         water/isopropanol mixture at a ratio of 2:3 and 5 g of a C₁₂₋₁₈         fatty alcohol-EO-BuO adduct with 8 EO and 8 BuO and mixed         intensely.

Example 2

Use of the gel produced in Example 1

Stainless steel germ carriers according to DIN 10510 were contaminated with Enterococcus faecium test organism in bouillon with an additional organic load of 1% mucin and 20% blood and left to dry for 2 hours at room temperature. The germ carriers were fixed in the spray mist tube of a dental suction apparatus, with one germ carrier at each of the front and far ends of the tube. For disinfection, the tube was wetted by suction of 200 ml of water; thereafter, 15 ml of a gel in accordance with Example 1, another 100 ml of water, and another 15 ml of gel according to Example 1 were sucked in.

Following a 60-minute exposure period, the gel was rinsed off by suction of 500 ml of water.

Subsequently, the germ carriers were removed from the tube, transferred into 10 ml of bouillon by shaking, and the colony number of this bouillon was determined by plating on agar plates.

In suitable comparative tests the gel according to the invention was replaced by

-   -   a) an aqueous solution having the same concentration of         identical antimicrobial agents, but     -   b) lacking the properties of thickening consistency in equal         amounts, relative to the concentration of the antimicrobial         agents.

The differences of the logarithms (basis 10) of the colony numbers found were determined as result (logarithmic reduction factor, logRf). The results are summarized in the following Table: Disinfection medium logRf Gel according to Example 1 >5.2 Aqueous solution according to Example 3.4 1 with no carboxymethylcellulose Water 2.5 

1-11. (Cancelled).
 12. A thickened, ready-to-use disinfectant composition for a medical or dental suction apparatus, the composition comprising an active substance having the formula

wherein R¹ represents an alkyl or alkenyl group with 8 to 18 carbon atoms and R² is selected from the group consisting of hydrogen, an alkyl group with 1 to 4 carbon atoms, an amino alkyl group with 2 to 4 carbon atoms, and Glucoprotarmin.
 13. The composition of claim 12, wherein the active substance is selected from the group consisting of Glucoprotamin, N, N-bis(3-aminopropyl)laurylamine, N-dodecyl-1,3-propanediamine, N-coco-1,3-propanediamine, and mixtures thereof.
 14. The composition of claim 12, wherein the active substance is present from about 0.01 to about 30 wt. %.
 15. The composition of claim 12, wherein the active substance is present from about 0.01 to about 15 wt. %.
 16. The composition of claim 12, further comprising a second active substance comprising a quaternary ammonium compound having the formula

wherein R⁵ represents an alkyl group with 6 to 16 carbon atoms, R⁶ is selected from the group consisting of a alkyl group with 1 to 12 carbon atoms, and a benzyl group, and R⁷ and R⁸ are selected from the group consisting of an alkyl group with 1 to 4 carbon atoms and a hydroxy alkyl group with 2 to 4 carbon atoms, and A⁻ represents a charge compensating anion.
 17. The composition of claim 16, wherein the second active substance is selected from the group consisting of benzalkonium chloride and dimethyldioctylammonium chloride.
 18. The composition of claim 16, wherein the second active substance is present from about 0.01 to about 30 wt. %.
 19. The composition of claim 16, wherein the second active substance is present from about 0.1 to about 15 wt. %.
 20. The composition of claim 12, wherein the composition has a pH from about 8 to about
 12. 21. The composition of claim 12, wherein the composition has a pH from about 9 to about
 11. 22. The composition of claim 12, further comprising a component selected from the group consisting of tertiary amine oxide, anionic surfactant, ether sulfates, alkylpolyglycosides, cationic surfactants, non-ionic surfactants, amphosurfactants, silicone defoamers, cumenesulfonate, xylenesulfonate, toluenesulfonate, hydrophobically modified polymers, diluents, chelating agents, enzymes, preservatives, sequestering agents, oxidizing agents, bleaching agents, dyes, perfumes, and mixtures thereof.
 23. The composition of claim 12, wherein the composition is effective at destroying a microorganism selected from the group consisting of a bacteria, a fungus, and mixtures thereof.
 24. The composition of claim 12, wherein the composition is effective at destroying mycobacteria.
 25. The composition of claim 24, wherein the mycobacteria are located in the suction tube of the medical or dental suction apparatus.
 26. The composition of claim 24, wherein the mycobacteria are located in the spitting cup. 